Hydraulic coupling type of variablespeed transmission



June 24, 1947. F. R. PORTER HYDRAULIC COUPLING TYPE OF "VARIABLE SPEED TRANSMISSIQN File d Oct. 26 1943 2 Sheets-Sheet 1 an" m I l I v 3 w Nm. H 1 1 a w v I ll WN w W m 0 a ma m. k% a NM: N

Junie 24, 1947. F. R. PORTER 2,422,850

HYDRAULIC COUPLING TYPE OF VARIABLE SPEED TRANSMISSION Filed Oct. 26,.1943 2 Sheets-Sheet 2 maintaining at varying 1 claims.

' in matters'oi shape,

atented June 24, 1947 HYDRAULIC COUPLING TYPE OF VARIABLE- SPEED TRANSMISSION Finley li. Porter, South Hampton, N. Y., assignor to Bendix Aviation Corporation, N. J., a corporation of Delaware Teterboro,

Application October 26, 1943, Serial No. 501,703

' 2 Claims.

ieinvention relates to improved means and methods forcontrolling speed difle'rentials between driving and driven members, and has par-- tieular reference to adlfl'erential drive or transmission for a rotating body such as a blower, ion or supercharger impeller, or other accessory driven "by an aircraft engine, wherein engine speeds vary according to do requirements.

necessaries, however, such as superchargers, are, due'tc constructional and operating char-= acteristics, limited for efficient operation to a lesser speed range than that provided by an airerait engine, even beyond the'two or more speed varying gear changes possible under the conventional structure.

object oi my invention, therefore. is to provide a'novel differential drive having automatic means for changing the operating characteristics thereof toconiorm to varying operatingi'equiremerits.

other ohiect of my invention is'to provide a control responsive to driving shaft s'peed for speeds of said driving elicit a are nearly constant torque and speed oi the driven shaft,

Another object of my invention is to provide novel means for automatically maintaining a nearly constant driven shalt speed upon the driving short rotating at varying rates of speed above a predetermined minimum.

Another object of my invention .is to provide a novel duid coupling arrangement having means for automatically varying the slippage oi the fluid coupling, as a function of driving shaft speed, to any predetermined ratio of driven shaft to driving shaft speed so as to maintain a. substantially constant driven shaft'speed and torque above a predetermined rate of speed.

a further object oimyinventionis to provide t see a driven shaft speed? control of great'efll-i eiency in (zomparisontditssizahnd oisuch 51m! novelmeans ior betweensqriying and driven .plicity; in'construction as to-adapt it for menu-- "torture and lnstallation at lowcost. p r g otiuer objector myjinvention is. to provide a 7 varyinga the amountroi coupling iiuid in a fluid transmissionjor regulating the ,transmlssion ratio elents.

' casing or housing other objects and advantages of this ifivesotm are set forth in the following description, taken with the'accompanyingdrawinss, and the novel features thereof are pointed out inthe appended The disclosure, however. is illustrative only and I may makeichauges in detail, especially I a shaft 2 charger indicated generally -roller bearings iii,

fat .ings (9 carried within a fixed sleeve 20. The sleeve 20 is mounted 2 iwithin the principle of the invention to the full extent indicated by the broad and general meanings of the terms in which the appended claims are expressed.

In the accompanyin drawings which form a part of this specification, like characters of reference indicate like parts in the several views, wherein:

Figure l is a sectional view of my novel constant speed fluid coupling drive.

Figure 2 is a fraentary end view of the novel constant speed control scoop of Figure 1.

Figure '8 isa fragmentary sectional view or a modified form of my constant speed fluid coupling drive and showing means for varying the speed thereoi. r

Figure 4 is a sectional view of Figure 8 taken along the lines t-d and looking in the direction of the arrows.

Figure 5 is a fr nentary top view of the constant speed control scoop of Figure 3.

Figure 6 is a fragmentary sectional view taken along the lines 6 of Figure 3 and illustrating the adjustable control means.

Referring to the drawings in detail and particularly to Figure l, the numeral I indicates a within which is rotatably mounted on roller bearings 2 and 3 a driving memher or shaft t. The shaft I has provided therein internal splines 5 for connection to a driving shalt of a conventional aircraft engine not shown. The driving shaft i has formed integral therewith a gear 6, which is arranged to intermesh with a gear i rotatably mounted on a stud 8 carried by roller bearings 9 and it. Formed integral with the gear 7 is a gear ii,which in turn intermeshes with a gear I 2. The gear I 2' is connected through splines it to a shaft it, rotatably mounted at one end in concentrically positioned withinthe gear t. r The opposite end of the shaft i4 is rotatably mounted in a sleeve it within bearing bushings ii and it. The sleeve i8 is rotatably mounted an end opposite from shaft ll in roller bear-' within the end of a casing 2!, which is in turn afilxed at the end of casing I by bolts it.

The sleeve l6 has internal provided therein suitable splines for connecting the sleeve I 6 to 24 for driving a blower,.fan or superby and which may he of any suitable typ .Well known in the art.

size and arrangement of parts 66 A fluid coupling unit indicated generally by the the numeral 25 numeral 2 iscarried by the shaft l4 and sleeve l6, and has a casing portion 21 connected with the shaft l4, while another casing portion 28 is connected to the sleeve l5 through Splines 28. The sleeve l5 as previously described is rotatably mounted on the shaft M by the bearing bushings l1 and I8.

Further spaced apart from the casing 28 are casing portions 38 and 3|, which are fastened to the casing portion 21 by bolts 32.

In general, the elements 21 and 28, when associated in the relation illustrated, constitute a toroidalchamber, one-half of which is connected to the driving shaft l4 and the other half of which is drivingly associated with the driven sleeve l8 through the splines 23.

A plurality of radial vanes 33 are mounted in the casing 21, while a plurality of similar vanes 34 are mounted in the casing 28 for providing a fluid coupling between the casing 21 and casing 28 when a suitable coupling fluid medium is within the toroidal chamber. The coupling 26 may be of a general character well known to the prior art and commonly known as the Fiittinger type of hydraulic coupling.

When the coupling fluid is not in the toroidal chamber, elements 21, 38 and 3| may rotate freely relative to the associate element 28, in which case there will be no drivebetween the shaft i4 and the sleeve l5. However, as the said-coupling fluid is admitted to the toroidal chamber, the vanes 33 carried by the element 21 will exert a centrifugal force on the fluid causing the same to actuate theelement 28 through the vanes 34 carried thereby.

The speed of rotation of the driven element 28 will depend upon the slippage between the driving and driven elements 21 and 28, and the speed of rotation of the driving element 21. Obviously the speed of rotation of the driven element may be kept at a relatively constant rate by varying the slippage in direct relation to the speed of rotation of the driving member, so that the greater the speed the greater the slippage between the driving and driven elements. Thus, the greater the speed of rotation of the driving member the greater the diil'erence in speedsbetween with the annular flange 31. It will be thus seen that there is provided by the plates 35 and 38 a receptacle or chamber stationarily mounted in relation to the revolving sump 3|. As will be explained, the receptacle 35 is arranged to carry a fluid medium for supplying the coupling 26.

The receptacle 35 has provided a duct 48, which opens into an annular channel 4| surrounding the sleeve IS. A second duct 42 formed inthe sleeve l5 opens at one end into the annular channel 4| and at the opposite end into an interior chamber 43 formed within the sleeve It. The chamber 43 is connected by a drilled passage 44 provided in shaft H to a duct 45 leading into the toroidal chamber. Thus it will be seen that the fluid medium may be conducted from the receptacle 35 to the coupling 28.

A port 48 of suitable size is provided in the casing 38 so the fluid medium within the toroidal chamber may be returned under centrifugal force to the fluid sump 3|. The return discharge through the port 48 increases as the centrifugal force increases, for a purpose which will be explained.

A novel inlet in the form of an automatic valve or scoop 41 is provided for controlling the passage of fluid from the sump 3| into the receptacle 35. The scoop 41 is positioned in an opening formed in the flange 31 at one side of the receptacle 35,

the two elements, and conversely the slower the speed of rotation of the driving member the less the difference in speeds between the driving and driven elements.

In order to accomplish this result, I have provided a novel means responsive to the speed of the driving member for controlling the supply of the coupling fluid medium delivered to the toroidal chamber.

Thus as shown in Figure 1, the casing 3| provides a tank or sump for storing the fluid coupling medium, which is separated from the toroidal chamber by the casing wall 38.

The tank or sump 3| is rotated with the casing wall 21 by the driving shaft f4 so that the fluid carried by the sump 3| is thrown by centrifugal force to the outer rim of the sump 3|.

For controlling the supply of fluid furnished the coupling 26 there is provided a fluid receptacle 35 fixedly mounted in relation to the revolving fluid sump 3|. The receptacle 35 includes an annular plate 38 formed integral with the fixed sleeve 28. The plate 38 has a flange 31 which projects at a right angle thereto and extends circumferentially around the same.

A second annular plate 38 is positioned in spaced relation to the annular plate 38 and fastened thereto by bolts 38 in sealing relation between the annular plates 36 and 38. The scoop 41 is aflixed to a bolt 48 pivotally mounted in the said plates 36 and 38 and extending transversely of the same as best shown in Figure 1. Aflixed to the bolt 48 is'an arm 49 positioned exteriorly of the receptacle 35. A tension spring 58 is connected at one end to the arm 49 and fastened at the opposite end to a-suitable fastening member 5| provided on the plate 36.

The spring 58 is arranged in such a manner as to bias the scoop 41 in a counterclockwise direction. A stop pin 52 limits the movement of the scoop 41 in response to the biasing effect of the spring 58 at the extreme vertical or maximum open position, as shown in Figure 2.

The scoop 41 has provided an arcuate walled portion 53 and an opening at 54. Positioned immediately above the opening 54 is an out-,- wardly projecting flanged portion 55 which serves as a deflector. Thus upon rotation of the sump 3| in a clockwise direction i relation to the receptacle 35, as viewed in Figure 2, the fluid me dium contained therein is'thrown by centrifugal force to the outer rim of the sump 3| so as to enter the scoop 41 at the opening 54. The fluid medium in the revolving sump 3| further exerts a. force upon the deflector 55 tending to bias the scoop 41 in a clockwise direction in opposition to the tension of the spring 58. Such clockwise movement of the scoop 41, as shown in dotted lines in Figure 2, will decrease the angle that the opening 54 makes with the fluid medium, and' thereby decrease the effectiveness of the scoop 41.

In the operation of my invention, the casing .the opening 54 in the scoop 41, which will be held in a full open position under the biasing force of the, spring 58. Moreover as the speed of the stant rate asaaaso F aircraft engine increases within the predetermined value, the supply oi fluid medium entering the opening 54 and passing into the receptacle 35 will increase with the speed of rotation of the driving member 4.

Further the rotation of the member 21 will cause through centrifugal force a suction force to be applied to the receptacle II through the duct 10, channel 4i, duct 42, chamber 48, passage 44 and duct 45, which will draw through said passages a fluid medium from the receptacle 35 into the-fluid coupling 26. I

As the fluid medium passes into the fluid coupling 26 the vanes 33 carried by the element 21 will exert a centrifugal force on the fluid medium causing the same to actuate the element 2a through the vanes it carried thereby.

Since the element 28 is connected by the splines 29 to the sleeve it, rotation of the element it will in turn cause rotation of the driven member 25. Moreover the fluid medium within the fluid connected to a manually operable control lever terclockwise direction the lever increasing the tension of the spring il whlle upon coupling it will in turn be discharged under s centrifugal force through the port 48 and returned to the fluid sump 3i.

As the speed of rotation of the aircraft engine increases, the speed of rotationot the driven member will be increased until the predetermined value is reached. A further increase in the speed of the driving mmber will then cause the fluid medium within the sump ti, under centrifugal force, to act upon the deflector it in such a manner as to biasthe scoop l'l in a clockwise direction, as viewed in Figure 2, in an amount dependent upon the speed of rotation of the driving member. Such movement of the scoop ll will thereby reduce the depth oi contact of the scoop ll in the fluid medium carried by the outer wall of the sump 3i, and likewise decrease the amount of fluid medium supplied to the receptacle and the fluid coupling 26. Further the discharge of fluid medium from the coupling 26 through the port 46 increases, asthe centrifugal of rotation of the sump 3|. Such action causes a decrease in the amount of fluid medium within the hydraulic coupling 26, thereby increasing the slippage between the driving member 21 and the driven member it, so as to increase the difference between the rates of rotation 01' the two members. When the said driving shaft speed decreases, the opposite cycle of forces act to increase the fluid. content of coupling it and reestablish the slip ratio between driving and driven members.

The mechanism is so arranged that upon the driving element rotating at a rate of speed in excess of a predetermined value, the rotation of the driven element will be kept at a relatively conby varying the slippage between the driving and driven elements, as described, in direct relation to the speed of rotation of the driving member.

In the second form of my invention in Figures 3, a, 5 and 6 I have shown illustrated varying the aforementioned of therate oi rotation of the driving member.

This is specifically accomplished by providing means for varying the biaslngj force exerted by the spring lid on the scoop 41. Thus rather than connecting the spring 50 to a flxed member ill as in the first form of my ventiomI have shown in Figures ii, 4, 5 and 6 the same connected to an adjustable arm 80 afiixed at the inner end of a shaft ti. The shaft tl' projects through a flxed sleeve it, which corresponds to the sleeve 20 force rises, on an increase in the rate all of the spring the scope of the invention. Reference 89, which may be conveniently mounted within the cabin of the plane. The control lever 89 is so arranged that upon moving the same in a coun- 60, as viewed in Figure 4, will be moved in a clockwise direction moving the control lever in a clockwise direction the tension of the spring 50 will be decreased.

Suitable means may be provided for locking the control lever 89 in any desired adjusted position.

From the foregoing it will be readily seen that upon increasing the tension of the spring W, a greater biasing force must necessarily be set up by the fluid medium within the sump l l, which is arranged to revolve in a clockwise direction, as viewed in Figure 4, before the scoop it may be biased so as to decrease the effective position thereof. Thus, a greater predetermined rate of rotation must be efiected before the constant speed maintaining mechanism will be brought into operation. Similarly by decreasing the tension at a lower predetermined rate of rotation of the driving member would be required for causing the operation of the constant speed maintaining mechanism. Likewise by vary-. ing the tension of the spring lit the maximum rate of rotation of the driven unit may be varied as desired.

From the foregoing, it will be readily seen that I have provided novel means ior'rnaintaining a driven member at a predetermined constant rate of speed, upon the driving member maintaining a rate of speed in excess of a predetermined value. Further, I have provided novel adjustable means for determining the said predetermined values.

Although only two embodiments of the invention have been illustrated and described, various changes in the form and relative arrangement of the parts, which will now appear to those skilled in the art, may be made without departing from is, therefore, to be had to the appended claims for a defla modified form of my invention embodying novelmeans torpredetermined value v of the accessory,

. of the engine element,

nition oi the limits of the invention.

What is claimed is: v

1. In hydraulic transmission apparatus adapted for operation between an aircraft engine and an engine accessory, the combination of a housing adapted at one end for mounting on the engine and at the other-end for attachment to the, accessory,v

nected' between said shafts speed? of saidsecond shaft relative to the speed thereto and adapted coupling member fixed to said second shaft and a second coupling member liked to' said driven shaft, means fixed to said first coupling member forming therewith the coupling fluid chamber. enclosing said second coupling member and also forming a sump outside said chamber having fluid communication therewith, a stationary hollow disc-like receptacle within said sumppand having a first shaft at said one end adapted forattachment to a rotativeenginew element, a seconddriving shaft, agear train confor increasing thea driven shaft telescopicalriy related to saidsecond shaft rotatable relative forattachment to a shaft 1 a fluid coupling including a first a radially inner support at said other housing end, said receptacle communicating at its radially inner portion through ducts in said driven shaft and said second driving shaft with said coupling chamber and having a peripheral open ing, a hollow scoop of substantially sector-shape pivotally mounted locally adjacent to the periphery of said receptacle for movement in said opening, said scoop facing the direction of rotation of said sump and having a deflector vane operated by the fluid in the sump for varying the position of the scoop and the rate of fluid intake thereof to the receptacle in accordance with the rate of rotation of the sump, and spring means connected between said scoop and said receptacle for biasing the scoop about its pivot oppositely to the direction of rotation of the sump.

2. In hydraulic transmission apparatus adapted for operation between an aircraft engine and an engine accessory, the combination of a housing adapted at one end for mounting on the engine and at the other end for attachment to the accesson]. a first driving shaft at said one end adapted for attachment to a rotative engine element, a second driving shaft, a gear train connected rotation of said sump and having a. deflector vane a operated by i the fluid in the sump for varying the position of the scoop and therate of fluid intake thereof to the receptacle in accordance with the rate of rotation of the sump, a pivot pin exbetween said shafts for increasing the speed 7 of said second shaft relative to thespeed of the engine element, a driven shaft telescopically related to said second shaft rotatable relative thereto and adapted for attachment to a shaft of the accessory, a-fluid coupling including a first coupling member fixed to said second shaft and a second coupling member fixed to said. driven shaft, means fixed to said first coupling member forming therewith the coupling fluid chamber enclosing said second coupling member and also forming a sump outside. said chamber having fluid communication therewith, a stationary hollow disc-like receptacle within said sump and having a radially inner support at said other housing end, said receptacle communicating at tending through said receptacle support between the interior and exterior of said housing at said other end, means including spring means connected-between said scoop and the inner end of said pin for biasing the scoop about its pivot 0ppositely to the direction, of rotation of the sump, and means outside {said housing operating through said pin for varying the tension of said spring.

FINLEY R. PORTER.

nnrsnnuons orren The following references are of record in the file of this patent UlHTED- STATES PATENTS 

